ellerbeck



DeC- 15, 1958 G. c. ELLERBECK DIVIDEND-DIVISOR ALIGNING MECHANISM 5 Sheets-SheefI 1 Filed May l2, 1953 Dec. 16, 1958 G. c. ELLERBECK DIVIDEND-DIVISOR ALIGNING MECHANISM 5 Sheets-Sheet 2 Filed May 12, 1953 Dec 13, 1958 G. c. ELLERBECK DIVIDEND-DIVISOR ALIGNING MECHANISM 5 Sheets-Sheet 5 Filed May 12, 1953 lmlmHlln-H Dec. 16, 1958 G. c. ELLERBECK DIVIDEND-DIVISOR ALIGNING MECHANISM 5 Sheets-Sheet 4 Filed May l2, 1955 Dec. 16, 1958 G. c. ELLERBECK DIVIDEND-DIVISOR ALIGNING MECHANISM 5 Sheets-Sheet 5 Filed May l2, 1953 United States Fatent DIVIDEND-DIVISOR ALIGNING MECHANlSll/i Grant C. Ellerbeck, San Leandro, Calif., assignor to Friden, Inc., a corporation of California Application May 12, 1953, Serial No. 354,603

Claims. (Cl. 23S-63) This invention relates to the division mechanism of calculating machines and more particularly to improved means for automatically aligning the divisor and the dividend incident to an automatic division operation.

In performing automatic division operations on machines of the type to be described, the dividend and divisor are relatively shiftable, one to the other. Whenever the number of digits in the dividend exceeds that of the divisor, the operator must cause the dividend register to be shifted until the highest significant digit therein is aligned with the highest significant digit of the divisor. The division mechanism is then set into operation by manipulation of a suitable control key or lever, whereupon the divisor is subtracted from the dividend until an overdraft occurs. With the overdraft, mechanism becomes effective to correct the overdraft and cause the dividend register to be shifted one ordinal position relative to the divisor. Following the shift cycle, the machine is again set for subtraction or a series of subtractions and each subtract cycle is counted positively in the revolutions counter including the cycle which creates the overdraft, however, with the correction cycle the count is reduced by "1 whereby only the true quotient is registered.

The instant invention discloses an improved automatic division mechanism whereby upon initiation of a division operation the dividend and divisor are automatically brought into alignment. During this alignment phase of the operation a partial quotient is registered in the revolutions counter, thereby reducing the number of machine cycles normally required for the division operation proper.

It is an important object of the present invention, when the highest significant digit of the dividend lies to the left of the highest significant digit of the divisor, to provide mechanism for suspending the initiation of division until these digits have been relatively shifted into an effective position, one with the other.

It is another object of the invention to provide a means for shifting the register of a calculating machine to operatively align the dividend with the divisor upon initiation of an automatic division operation and preliminary to the computation proper.

It is another object of the invention to provide a mechanism for automatically aligning a dividend and divisor in a calculating machine upon manipulation of a single control key and to thereafter effect initiation of an automatic division operation.

lt is another object of the invention to provide a mechanism under the control of a single key for initiating a` right shift of the dividend register to a position predetermined by the divisor and effective in this position to terminate the right shift and initiate an uninterrupted series of sequential functions intrinsic to an automatic division operation.

It is another object of the present invention to provide a means controlled by the automatic division mechanism of a calculating machine for deferring the functions thereof which banks is illustrated in part in Fig. 1.

Patented Dec. 16, 1958 fice of until the dividend and divisor are shifted into effective interrelation, one with the other.

lt is a further object of the invention to provide a mechanism controlled by the manipulation of a control key for superseding an automatic division operation until the register value has been ordinally shifted to a predetermined position relative to the keyboard value with each machine cycle being registered in the quotient register in each ordinally shifted position of the register.

It is another object of the present invention to provide an improved automatic division mechanism which operates precedentially to a division operation to align the highest significant order of the dividend with that of the divisor and to effect a partial registration of the quotient during the aligning phase of the operation.

The invention further resides in the combination, construction, and arrangement of parts illustrated in the accompanying drawings, and while there is shown therein a preferred embodiment thereof, it is to be understood that the same is illustrative of the invention and that the invention is capable of modification and change and comprehends other details of construction without departing from the spirit thereof.

in the drawings:

Fig. l is a longitudinal sectional elevation showing the basic mechanism of the machine.

Fig. 2 is a fragmentary elevational View of the right side frame showing the clutch and driving gear train.

Fig. 3 is an elevational view of the right side control plate as viewed from the left.

Fig. 4 is a fragmentary plan view of the right side of the machine showing the actuating and shift mechanism.

Fig. 5 is an elevational view of the right side control plate, asy viewed from the right, showing a portion of the automatic division control mechanism.

Fig. 6 is an elevational view of a portion of the division aligner control mechanism taken on the line 6-6 in Fig. 4.

The machine to be hereinafter described is basically the same as the calculating machine shown in the Patent No. 2,229,889 issued to Carl M. F. Friden, January 28, 1941. The instant invention, however, is an improvement of the automatic division mechanism disclosed in the Patent No. 2,327,981 issued to Friden, August 31, 1943 and includes the mechanism of Patent No. 2,294,111 issued to Friden, August 25, 1942. Hence, only so much of the mechanism shown and described in the aforesaid patents will be set forth herein as is necessary in order to provide a complete understanding of the manner in which the present mechanism is related to that shown in the aforementioned patents.

Selecting, actuating and accumulating mechanisms The machine includes base 10 (Fig. 1) which supports casing 11 and has side frame members 12 and 13 (Figs. 1 and 2) mounted thereon. Side members 12, 13 are connected by various crossframe members 16, 17, 18 and 19 (Figs. 1 and 4) which serve to mount various mechanisrns referred to hereinafter. The accumulator register comprises a series of reversible numeral wheels 21 (Fig. 1) in register carriage 22 which is mounted on frame members 16 and 19 by rollers 23 for endwise shifting movement laterally of the machine in either direction, to various ordinal positions. The values to be introduced into numeral wheels 21 are selected by means of a plurality of banks or orders of settable value keys 26, one. Each bank of keys 26 cooperates with selecting mechanism including a pair of spring-urged slides 27 mounted for endwise movement to position the associated pair of gears 28 selectively with respect to the stepped teeth (not shown) of the associated actuating drum 29, in accordance with the value of thejdepressed key. Drums, or cylinders, 29 (Figs. 1 and 4) are mounted on actuating shafts 31 having suitable bevel gear connections with transverse, or driving, shaft '32Vwhich is suitably journalled in side members 12 and 13. Each shaft 31 serves two orders of the machine and 4has a pair of drums 29 mounted thereon. Shaft 32 and shafts 31 are driven unicyclically from motor 33 through clutch 34 (Fig. 2) which is driven by suitable gearing 35 from motor shaft 36. As explained in the aforementioned Patent No. 2,229,889, clutch 34 is engaged or disengaged by oscillation of spring-urged clutch pawl, or dog, 37 mounted for rotation with driving gear 35 with respect to a ratchet (not shown) on shaft 32. Clutch control lever 39, pivoted on side member 13, determines engagement or disengagement of the clutch by releasing or engaging clutch dog 37 in the full-cycle position thereof.

From the above description -it is seen that the values set in the machine by depression of keys 26 will -be introduced into numeral Wheels 21 by the cooperation of gears 23 with cylinders 29 during cyclic operation of the clutch. Each pair of gears 28 is slidably mounted on a square shaft 41 (Fig. 1) supported in cross-members 17, 18 extending rearwardly of the machine through crossmember 17 and having its rear end journalled in crossmember 16. Intermediate members 16 and 17, a spool 42 is slidably and nonrotatably mounted on each shaft 41 and has opposite bevel gears 46, 47 at its ends positioned for cooperation with numeral wheel gear 48 mounted at the lower end of numeral wheel shaft 49 journalled in the frame of carriage 22. Therefore, when one set of gears 46, 47 is engaged with gears 48, numeral wheels 21 will be rotated forwardly or reversely to register a number of Vincrements equal to the value of the depressed keys 26 in the aligned banks of keys.

Plus and minus keys Means are provided for selectively determining positive or negative registration on the numeral wheels 21 in the form of plus key 56 (Fig. 3) and minus key 57, which are slidably mounted on control plate 58. Depression of either of keys 56, 57 serves t0 engage the clutch, close the motor circuit, and select the sign character of the registration. To enable the drive, keys 56, 57 have respective pins S9 in operative relation with suitable cam surfaces on clutch actuating lslide y61 mounted for end` Wise movement on plate 58. To effect control of the clutch by such movement, pin 62 on the upper arm of clutch control lever 39 (Figs. V2 and V3) abuts the rear end of'slide 61- so that `rearward movement of slide 61 oscillates lever 39 in a clockwise direction, as viewed in Fig. 2, to release clutchdog 37 for engagement with the ratchet on shaft 32. To close the motor circuit, the rearward movement of pin 62 serves, through link 63, to rock lever 64 clockwise about its pivot on side member 13 and through a connection at its lower end with lever 66, also pivoted on member 13, rocks the lever 66 counterclockwise. Lever 66 has a suitable insulated pin in overlapping relation with spring-mounted contact 67 normally spaced from similar contact 68. To determine the sign character of the registration, plus and minus keys 56, 57 (Fig. 3) have respective rollers 71 disposed in operative relation with opposed cam surfaces 72 on plusminus slide 73. Slide 73 is mounted for endwise movement at its front end by an arm 74 pivoted on plate 58 and at its rear end by an arm 76 on shaft 77 (Figs. 3 and 4), which is suitably journalled in side members 12, 13. Shaft 77 carries transversely extending strap 78 (Figs. l and 4) which is positioned between gears 46, 47 so that rocking movement o-f-shaft 77, under control of plus-v minus slide 73, serves to determine engagement of gears 46 or 47 with numeral wheel gears 48, or to determine the disengagement thereof, as in the position shown. Thus, depression of plus key S6 by meshing gears 46, 48 and enabling the drive, determines one, or more posi-4 tive registrations of the values set in the keyboard on numeral wheels 21. Similarly, depression of key 57 determines one or more negative registrations of such values by meshing gears 47, 48.

Accumulator transfer mechanism Means are provided for carrying from order to order in the accumulator register when the registration of a numeral wheel 21 changes from "0 to 9 or vice versa. For this purpose, each numeral Wheel shaft 49 (Fig. l) carries a single tooth gear 81 immediately beneath the frame of the carriage 22 in operative relation with a nose of the transfer lever S3 pivoted at 84 on the carriage frame. Lever 83 is retained in the carriage frame by a spring-pressed ball engaging a suitable notch in the pivot 84. Each lever 83 extends into the next higher order of the machine and carries a downwardly extending portion 87 in operative relation with flange 89 on collar 91. Gear 92 on collar 91 is normally disposed out of the path of single tooth actuator 93 on shaft 31. When numeral wheel 21 of one order passes from "9 to "0 or vice versa, the single tooth gear 81 rocks lever 83, which, through nose 87, moves collar 91 to position gear 92 of the next higher order in the path of the associated transfer actuator 93. Thus, the transferred increment is introduced through either gear 46 or 47 of the next higher order depending upon setting of the machine for addition or substraction. Transfer gear 92 is maintained resiliently in either adjusted position thereof by the engagement of flange 96 of collar 91 between spaced flanges 97 on stub shaft 98 slidably mounted in cross-members 101, 192 and engaged by a suitable spring-pressed ball (not shown). Suitable restoring means is provided for the shiftable transfer mechanism in association with transfer actuator 93 as fully disclosed in the aforementioned patent No. 2,229,889.

Revolutions counter A revolutions counter is also provided to register, positively or negatively, the number of actuatious of accumulator numeral wheels 21. Revolutions counter numeral wheels 106 (Fig. l) are suitably journalle'd in carriage 22 andare actuated by the counter actuator, shown generally at 1117, on shaft 108, to register the number of positive and negative registrations on numeral Wheels21, as fully disclosed in the above-mentioned patent. A part of the driving means for the revolutions counter actuator 1117, as disclosed in said patent, is indicated schematically at 109 in Fig. 4, while a portion of the-sign character control means therefor is shown at 110 in Pig. 5. The control means 111) is selectively operable in van automatic division operation to cause a quotient registration of a like or unlike sign character with 'respect'to the registration in the accumulator numeral wheels 21, as will be more fully described hereinafter.

Carriage shift mechanism Means are provided for shifting the carriage bidirectionally from one ordinal position to another by powerdriven means controlled by manually operable keys. The power-driven means includes a part of the actuating means for entering values into the accumulator register. Carriage 22 (Fig. l) has a plate 111 suitably mounted along the rear side thereof, and conventionally provided with equally spaced vertical slots therein. These slots are adapted for engagement by shift pins 112 on shift gear 113 suitably journalled on crossframe member 16. The shift gear 113 is rotated selectively in either direction through idler gear 114 to shift the carriage through any desired number of ordinal spaces by the cooperation of pins 112 and the rack 111.

In order to rotate shift gear 113 selectively in either direction, the two right-hand actuating shafts 31 (Fig. 4) are extended and are provided with similar controllable drive connections with gear 113. Each connection includes a collar 121) and 121 aftixedon its associated shaft 31 adjacent the end thereof and having opposite slots slidably engaged by corresponding dogs 122 and 123, respectively, of shiftable collars 124 and 125, which are mounted for sliding movement at the end of said shafts 31. Collars 124, 125 have smaller dogs 126, 127 in operative relation with corresponding slots in gear sleeves 128 and 129. Gear sleeve 128 is suitably journalled in cross-member 16 and plate 130 and carries gear 131 meshing with idler gear 114 to eflect a left shift of the carriage 22. Similar gear sleeve 129 has gear 136 which meshes with wide gear 137 (Figs. l and 4), also in operative relation with idler gear 114 to effect a right shift of the carriage 22. Thus, by selective shifting of collars 124, 125 to establish a drive connection, rotation of actuating shafts 31 determines rotation of shift gear 113 in either direction and correspondingly shifting of the carriage 22 in either direction. Similar mechanisms are provided to control shifting of collars 124, 125. Each mechanism includes a fork 138, 139 at the rear end of respective rods 146 and 141, and engaging their associated collars 124, 125. Push rods 140, 141 are slidably mounted in cross-members 17, 18 and are spring-urged to the position shown by a spring 142. Rods 149, 141 (Figs. l and 4) have associated therewith, respective arms 143 which are oscillated to shift rods 140, 141 by means including well-known keys (not shown) mounted for endwise movement on the side member 13 and also suitably connected to engage clutch 34 and close the motor circuit. Thus, carriage 22 carrying numeral wheels 21 can be shifted selectively bidirectionally upon depression of conventional shift keys.

Division control mechanism The above-described mechanisms cooperate with mechanism about to he described in performance of plural order machine operations in solving problems in division. The conventional method of division is used, which comprises repeated subtraction until an overdraft, correction of the overdraft, and shifting of the dividend register to the next lower order, where the process is repeated. The number of subtractions in each order is registered in the revolutions counter as the quotient. The mechanism disclosed herein for performing division by the above method, provides programmed operation of the machine under control of a program control device, which, upon each overdraft in the dividend register, initiates a predetermined sequence of operations during uninterrupted cyclic operation of the actuating means. As will be more apparent later, the structure provided herein provides for a minimium time consumed by a given division operation, as the drive for the actuating means is not stopped, even momentarily, from the beginning until the end of the operation, and as a minimum number of cycles of the actuating means is utilized during functioning of the program control device. The division operation is initiated by manipulation of a division starting `control lever which enables the program control device with respect to the plus-minus control of the machine and with respect to the overdraft mechanism. For convenience in description, the setting of the machine for division will be described first.

The division starting control is operative first, to connect the program control device to the plus-minus control of the machine and to the overdraft mechanism, as Well as to condition the clutch for engagement. The subsequent return of the starting control to its normal position engages the clutch and closes the motor circuit to start the operation.

As shown in Fig. 3, a division control key 158 is supported by a longitudinally disposed pair of elongated slots 151 for endwise sliding movement on the coacting guide studs 152 carried by control plate 58. Key 150 is normally urged to its raised position by means of a suitable return spring 153 and is provided with an inclined cam face 154 which bears against the roller 155 mounted yon a division control slide 156. This slide is supported forv endwise sliding movement on control plate 58 by a pair of studs 157 engaging in elongated slots 158. As shown in Fig. 5, there is pivotally mounted at 162 on the control plate 58, a latch 163 for holding thepower-operated division actuator' 164 in the position shown in Fig. 5 until released by the depression of the key 150. This latch 163 is urged counter-clockwise (Fig. 5) by the resilient action of a spring 165 anchored at one end to the lower extremity of latch 163, and at its other end to a stud 166 mounted on control plate 58. The resilient action of'spring 165 normally maintains a shoulder on latch 163 beneath a roller 167 mounted on the forward end of the power-operated division actuator 164, which is pivotally supported at 168 on the control plate 58. The actuator 164 is urged to rotate in a counter-clockwise direction (Fig. 5) by the resilient action of a relatively stro-ng spring 169 tensioned between the actuator and the stud 166 in such a manner as to urge the roller 167 into engagement with the shoulder on the latch arm. Likewise, spring 165 serves to retain the nose of a forwardly extending arm 170 of latch 163 in engagement with a roller 171 on the division control slide 156. Thus, when slide 156 is moved rearwardly with the depression of key 150, the shoulder of latch 163 is moved out of engagement with roller 167 and allows the actuator 164 to be rocked counter-clockwise by the resilient action of the relatively strong spring 169. Actuator 164 will be thereafter immediately restored to its initial position in the first machine cycle by the cam action of a roller 172 secured to the face of a gear 173 which rotates with the shaft 32. The roller 172 is operable to engage a cam face 174 formed on an upwardly extending arm of the actuator in such a manner as to rock actuator 164 clockwise against the urgency of spring 169 and thereby permit latch 163 to reengage with the roller 167.

Lying beneath the forward end of actuator 164 is a roller 176 (Figs. 3 and 5) carried by the lower end of a link 177 which is pivotally connected, as at 178, to the forward end of a division setting lever 179, which lever is pivoted at 180 on arm 181 pivotally supported at 182 on plate 58. Arm 181, as later described, forms a part of the program control device and is oscillated to control machine operation. Pivotally connected to the upper end of link 177 is the rearwardly extending arm of a bellcrank lever 183 pivotally supported at 184 to control plate 58. Lever 183 has an upwardly extending right angle extension 185 which lies immediately in front of a pin 186 carried by the clutch actuating slide 61. The lever 183 is urged clockwise (Fig. 3) by= a spring 187 in such a manner as to normally maintain link 177 and roller 176 thereon in a raised position for engagement of roller 176 with the arm of actuator 164. From the foregoing description it may be seen that with the release of latch 163 (Figs. 3 and 5), spring 169 is eifective to rock division actuator 164 c-ounter-clockwise about its pivot 168. With the Counter-clockwise rocking of division actuator 164, link 177 serves to rock division setting lever 179 clockwise and bellcrank lever 183 counterclockwise to move clutch-engaging slide 61 rearwardly to engage the clutch and effect closing of the motor contacts. Such clockwise movement of setting lever 179 serves to connect the program control device with plusminus slide 73. For this purpose, the rearward end 188 of lever 179 is provided with a bifurcation 189 formed by an upwardly extended portion 190 of the rearward end 188 and a yieldable pawl 191 adapted to engage pin 192 which is adjustably secured on plus-minus slide 73. Pawl 191 is pivotally supported at 193 on the rearward end 188 of division setting lever 179 and carries an ear 194 formed at right angles thereto for engagement with the leading edge of the rearward end 188. A spring 195 serves to maintain pawl 191 in the normal position shown in Fig. 3, but'will yield, however, when plus-minus slide 73 iS moved rearwardly by means of mechanism to be 7. hereinafter described. The movement of setting lever 179 to engage the bifurcation 189 with pin 192, serves to move slide 73 forwardly by virtue of the inclined edge of the pawl 193i adjacent the notch lh with the coopera-- tion of the relatively strong spring MS, thereby rocking shaft 77 and meshing gears 47, 48 so that the machine is set for subtraction. This action occurs because of the position of pivot ldd for setting lever lll, as determined. by the three-position control cam 200 on shaft 201 of the program control device. Cam Ztl/'0 engages an aperture Zim in arm ll and is rotated in a manner described later, to adjust the machine for addition or subtraction.

Clockwise oscillation of connecting or setting lever i7@ also serves to enable the over raft mechanism with respect to the program control device. A pin 263 (Fig. 3) on rear arm ldd of lever 179 is disposed beneath an arm 2d@ o-n the right-hand end of transverse shaft 2&5 journalled in control plate 5?, side member f3 and bracket 206 mounted on cross-member lill. Adjacent bracket 2do (Fig. l), shaft 2de" has an arm 2d? secured thereon having a pin 203 disposed in a slot 209 in a link 2li?. Link 2li) is pivotally supported at its upper end on a bracket 2li secured on the extended end of the transfer stub shaft 93 of the twelfth order of the machine. Link 2l@ is urged to the inoperative position thereof shown in Fig. l, by a spring 212 which normally maintains the free end of link 2l@ below depending plate portion 2l3 of lever member Elf-l, rotatably and nonslidably mounted on shaft 201i of the program control device. Upon clockwise oscillation of lever 179-, pin 203 rocks arm 294, shaft 2615 and arm 267 to lift link 210 into operative position with respect to plate portion 213 of lever member 2M. Latch means becomes effective to latch the settable parts in their above-described adjusted position for the duration of the division operation in a well-known manner.

Preferably, the latch means is associated with connecting lever 179 and maintains said lever in its adjusted active position until the end of the division operation or until such operation is interrupted by the operator, as is more fully described in the aforo-mentioned Patent No. 2,327,98l. Adjacent its rear end, lever 179 (Figs. 2 and 3) has a Hat bottom extension of pivot pin i9?, projecting therefrom in operative relation with latch lever, or member, 223 pivoted at 219 on side member 13 and urged in a clockwise direction, as viewed in Fig. 2, by a spring 224i. When lever f7?! is moved by division actuator leftupon release of latch 163, pin 193 moves upwardly, rocking latch member Bld until pin 193 rises above latching face 221 on member 2id. Spring 22d then becomes effective to move face 221 beneath pin TNF, whereby lever f7@ and the parts adjusted thereby are maintained in operative relation. Thus, arm 181 of the program Control device, setting lever 179, plus-minus slide 73, and latch member 218 are latched together for movement as a unit, slide 73 having been adjusted to its minus or subtractive position. Also, overdraft control link 2X0 (Fig. l) has been moved into operative relation with member 2M of the program control device. The above-described conditioning is effected entirely by the rocking of division actuator ldd. Thereafter, when the operator releases key lStl, division actuator ldd, latch member i623 and key 50 are returned to normal positio-n under the influence of their respective springs.

When the machine starts operation, the divisor set in the keyboard is subtracted repeatedly from the dividend entered in the accumulator, or dividend register, with thc carriage positioned in a manner to obtain the highest order digit of the quotient. The mechanism for so positioning the carriage automatically will be described hereinafter. When the divisor is subtracted once too often, the resulting overdraft causes forward movement of the extended transfer shaft 9S of the twelfth order after approxin'iately 200 ofl the overdraft cycle. lnasmuch as the main transfer mechanism is mounted within the framework of the machine and is contained in the space existing between the right and left side frames of the machine, the first twelve orders of the register may be considered to be the inboard orders thereof when the register carriage is yin its leftmost, or normal, position, whereas all higher orders of the register may be considered to constitute the outboard orders of the register. The forward movement of the twelfth order transfer shaft 98 is utilized through the overdraft controlled means to condition the machine for initiation of operation of the program contro-1 device, the actual initiation thereof, however, being effected by an element of the actuating means. Upon an overdraft, extended transfer shaft 98 and link 2li@ (Fig. l) move forwardly and as link 2li? has been moved into operative relation with plate portion 2l3 of member 2id. member 211i is rocked in a clockwise direction, as viewed in Fig. 1, against the influence of a spring (not sho-wn) which normally maintains tail Z22 of member against shaft 205. Such Iclockwise movement of member 25,6.'- moves an upwardly extending cam arm 223 of member 2M into the path of a roller, or pin, 224. on a disk 225 which is secured on the highest order actuating shaft 3l. rfhus, the overdraft control means conditions the program control device for operation, such conditioning 'taking place after approximately 300 of the overdraft cycle.

Immediately after cam arm 223 is moved into the path of roller 22d, it is engaged thereby to shift member .2M- and shaft 2011 to the right, as viewed from the front of the machine, to start operation of the program control device. Thereafter, the program control device determines a predetermined sequence of operations including correction of the overdraft, shifting of the register carriage to the next lower order, and resetting of the machine for subtraction.

The program control device, which, in the typical example shown, may comprise the shaft Ztll (Figs. l, 3, and 4) and cams 200 and 22d thereon, exercises its control by virtue of intermittent rotation of certain parts thereof, including shaft 203i, during the overdraft cycle of the machine and the two succeeding cycles of the machine after which the device is automatically disabled. To produce the intermittent movement of shaft Ztll, a gear 227 (Figs. 4 and 5) is mounted on the end of shaft 201 which projects beyond the right-hand side of control plate 5d. Gear 227 is normally in the inoperative position shown, out of the path of cooperating mutilated gear 228, which is driven cyclically through gears i173, 229 from shaft 32. Such inoperative position is determined by a notch in the gear 227 engaging over pin 230 on plate 58 under the urgency of a conventional spring at the left end of shaft As seen in Fig. 5, gear 227 has three equally spaced sets of three teeth each for cooperation with a single set of two teeth provided on gear 223. This gear 22d rotates in a counter-clockwise direction, as viewed in Fig. 5, and its teeth are positioned to engage a set of teeth of gear 227 immediatety before the end of a cycle. The arrangement is such, therefore, that when gear 227 is projected into the path of gear 223 during a cycle of operation, gear 227 is rotated one-third revolution starting near the end of thatv cycle and also one-third rotation at the end of each o-f the two next succeeding cycles, being maintained in projected position by the engagement of pin 230 with the inner face of gear It will be recalled that upon an overdraft, cam arm 223 (Fig. l) is moved into the path of roller 224 so that shaft 2M is moved to the right and gear 227 is placed in operative relation with gear 223. rl'hus, the first onethird rotation of shaft Zilli starts just before the end of the overdraft cycle, but is not actually completed until after the start of the next cycle but before digitation begins in the next cycle. This first one-third rotation of shaft 291 is utilized to change the setting of the machine from subtraction to addition, so that the next cycle of the actuating means will cause a correction of the overdraft. As described previously, eccentric cam 200 (Fig. 3) is normally positioned to condition the machine for subtraction with the movement of the plus-minus slide 73 forwardly of the machine, upon operation of the division key 150. setting slide 156 for releasing division actuator arrn 164, and the clockwise rocking of division setting lever 179. The one-third rotation of shaft 201 at the end of the overdraft cycle moves the three-position cam 200 through an angle of 120 in a counter-clockwise direction, as viewed in Fig. 3, and such movement results in rearward movement of arm 181 and division connecting lever 179 as link 177 merely oscillates about its pivotal connection with bellcrank 183 without changing the adjustment of the bellcrank 183.

Thus, the operation cycle after an overdraft cycle serves to correct the overdraft. At the end of the corrective cycle, the second one-third rotation of cam 200 and shaft 201 occurs and determines a carriage shift cycle of the machine. This is effected by setting plus-minus slide 73 to its neutral position where both gears 46, 47 are out of mesh with gears 48, as illustrated in Fig. l, and by engaging the drive connection to determine a one-step shift of the carriage to the left. The second one-third rotation of shaft 201 (Fig. 3) moves cam 200 counter-clockwise another 120 where a slight clearance is provided in arm 181 so that lever 179, plus-minus slide 73 and gears 46, 47 can be centralized quickly in neutral position under the urgency of a spring 231. Means are provided for engaging left-hand shift collar 124 (Fig. 4) with gear sleeve 126 during said second one-third rotation of shaft 201. A cam 226 fixed on shaft 201 adjacent the righthand side member 13 is normally positioned out of alignment with an arm 235 on shaft 236. Shaft 236 is suitably journalled in side members 12, 13 and carries arm 237 which extends upwardly and rearwardly so that its end abuts left-hand shift fork 138 (see Figs. l and 4). When the program control device is enabled by shifting of shaft 201, cam 226 is moved into alignment with arm 235. Cam 226 is so positioned angularly on shaft 201 that it is effective to rock arm 235, shaft 236, and arm 237 to engage collar 124 with gear sleeve 128 during said second one-third rotation of shaft 201. Such engagement is maintained for one cycle of operation of the machine and effects one ordinal spacing of the carriage.

At the end of the shift cycle, shaft 201 receives its third one-third rotation to restore the program control device to its original condition, cam 200 (Fig. 3) being rotated a third 120 to reset the machine for subtraction, and shaft 201 being moved to the left, as viewed in Fig. 4, by its spring (not shown) and the notch in gear 227 (Fig. engaging over pin 230. As a result, subtraction begins in the shifted position of the carriage until an overdraft, when the program control device is again placed in operation, as described above.

Revolutions counter control mechanism In a division operation it is most often desirable that a true quotient be had, i. e., that the sign character of the registration in the revolutions counter be unlike the registration in the register. However, there are occasions when the operator desires a negative quotient when the registration in the revolutions counter and the dividend register will be of like sign character. Means are provided for selective control of the quotient registration and for this purpose a key 240 is mounted adjacent division .control key 150 for endwise sliding movement by slots 241 embracing studs 242 on control plate 5S. Key 240 vis normally urged to the inoperative position shown in Fig. 5 by a spring 243. A lever 244 is pivotally mounted :at 245 on control plate 58 and has an inclined cam surface at the lower extremity thereof for cooperation with .a roller 246 mounted on the lower end of key 240. At its upper extremity, arm 244 has a link 247 pivotally secured thereto at 248 and is normally urged into engage- 10 ment with roller 246 by spring 249. At its rearward end, link 247 has a pin-and-slot connection with a lever 250 pivoted at 251 on control plate 58 which is rockable counter-clockwise upon depression of key 240.

The sign character of the registrations in the counter is selectively determined by the counter control mechanism (Fig. 5) which comprises a counter setting member 254 having respective upper and lower notches, or seats, 255 and 256 for engagement by the respective pins 257, 258 carried at the forked end of an arm 259, which is pivoted at 260 to the rearward end of plus-minus slide 73. A spring-urged centralizer 261 is provided for member 254. Arm 259 is normally spring-urged downwardly by spring 262 to engage pin 257 with seat 255 of member 254. It will be seen that the engagement of pins 257 and 25S, in their corresponding seats 255, 256, determine the direction of rocking movement of member 254 from its centralized position in response to a given movement of the plus-minus slide 73, so that the direction of registration on the revolutions counter can be reversed with respect to a given direction of registration on the accumulator. With the arm 259 in the norrnally spring-urged position shown in Fig. 5, each registration in the counter will be like that in the accumulator.

Whereas, if arm 259 is rocked clockwise to engage pin 258 with its seat 256, each counter registration will be unlike that in the accumulator.

As previously stated, optionally operable control means are provided whereby the operator can, if he desires, set the machine to provide for a positive quotient in the revolutions counter during division operations, so that it is very convenient for the operator to obtain true figure results in the quotient. The juxtaposed relation of the key 240 with the division key is such that the two can be easily operated together by a single manual stroke, or the division key can be operated alone if so desired. As seen in Fig. 5, lever 250 has a foot 263 extending therefrom and underlying pin 257 of arm 259 so that counter-clockwise rocking of lever 250 serves through the foot 263 to raise pin 257' from its seat 255 and engages pin 258 with its seat 256. Therefore, it can be seen that upon simultaneous depression of keys 150 and 240, the forward and rearward movement of plus-minus slide 73 is efective to cause an unlike sign character registration in the counter with respect to the accumulator. A latch member 264 is provided for cooperation with pin 265 on lever 250 and is Operative, upon the initiation of a division operation, to maintain arrn 259 in its adjusted position. t is believed that the operation of the counter control mechanism will be apparent from the foregoing description, however, for a more complete description thereof, reference is to be had to the aforementioned Patent No. 2,294,111.

Dividend aligning mechanism In performing automatic division operations it has heretofore been necessary for the operator to first set the dividend in the keyboard and to then depress the plus bar to transfer the dividend to theregister. The operator must then place the divisor in the keyboard in such a manner that the highest significant digit of the divisor is aligned with the highest significant digit in the dividend, to be followed by a depression of the division key. In machines incorporating the automatic dividend entry mechanism disclosed in Patent No. 2,403,273 issued to Carl M. Friden et al., July 2, 1946, the dividend may be entered and the register selectively tabulated to a predetermined position. However, with either means of dividend entry the operator is required to set the divisor in the keyboard in the manner described supra. If the operator has inadvertently set the divisor in the keyboard so that the highest significant digit thereof lies to the right of the highest significant digit of the dividend, or if the results of a previous computation is to become a, dividend, and the highest value or digit thereof lies to the left of a divisor locked in the keyboard, the operator must shift the register to a position where each of these values are properly aligned. With the mechanism to be hereinafter described, the operator has but to enter the dividend in the accumulator and place the divisor on the keyboard, irrespective of the position of the dividend register, and depress the division key.

Upon depression of the division control key 154i, means becomes immediately effective to centralize gears 46, 47 with respect to gears 48 and to enable an ordinal shift of the register to the right followed by a single subtraction of the divisor from the dividend, which sequence of operations continues successively until an overdraft occurs. ln the programming of a subtract operation in each ordinally shifted position of the register, a portion of the subsequent quotient is registered in the revolutions counter. rlhe dividend aligner programming mechanism disclosed herein provides operation of the machine under control of a bi-cyclic program control device. As will be more apparent later, the provision of the structure described herein provides for a minimum time consumed by a given division operation since the depression of a single control key is effective to initiate a dual operation which previously required the depression of two keys. For convenience in description, the automatic division mechanism was hereinbefore described since a portion of this mechanism is utilized in the function of the dividend aligner control mechanism.

It will be recalled that depression of division control key 15@ operates first to connect the division program control device to the plus-minus control or" the machine and to the overdraft mechanism as well as to condition the clutch for engagement. Manipulation of the control key 156i also serves to condition the bicyclic program control device to effect a shift cycle and a subtract cycle in each ordinally shifted position of the register, which bicyclic program continues successively to an overdraft.

For this purpose, a gear 271D is secured to one end of a shaft 271 journalled for laterally sliding movement in side frame 13 and control plate S8 (Figs. 4 and 5). The gear 270 has two sets of four teeth each for meshing engagement with four teeth of a mutilated gear 272 secured to driving gear 229 with which mutilated gear 223 is also operatively associated. Gear 270 is normally in the inoperative position shown in Fig. 4, that is, to the right of the mutilated gear 272 which is driven cyclically through the gears 173, 229 from. shaft 32. As gear 272 rotates in a counterclockwise direction, as viewed in Fig. 5, its teeth are positioned to engage a set of teeth of gear 27@ immediately upon the beginning of a cycle of machine operation. The arrangement is such, therefore, that when gear 271B is moved into the path of gear 272 upon initiation of a division operation, gear 270 is immediately rotated one-half revolution at the outset of the first cycle and a second one-half revolution at the outset of the next succeeding cycle.

To control the lateral movement of the gear 270 and shaft 271, a forked member 273 (Fig. 5) is hinged on a spindle 274 in a bracket 275 secured to control plate 5S for movement toward and away from plate 58. The lower arm of forked member 273 is bifurcated to engage an annular groove in the hub of the gear 2711 to control the movement thereof, while the lupper arm 276 of member 273 is axially aligned with the program control shaft 2111 and normally spaced therefrom a distance suflicient to permit movement of the gear 27@ into the path of the mutilated gear 272. A leaf spring detent 277 secured to control plate 55 has an outwardly extending portion at right angles thereto for engaging in an aperture 278 of the member 273 to retain member 273 in either its operative or inoperative position.

It will be recalled that upon depression of division control key 151B (Fig. 3), division setting slide 156 is moved rearwardly to release latch 163 when spring 169 becomes effective to rock division actuator 164 counter-clockwise.

Division actuator 164 has a rearwardly extending linger 279 which becomes operative with the rocking movement thereof, to engage a cam 230 formed in the lower end of a depending portion 281 of the forked member 273 to move member 273 inwardly of the frame 53 and thereby align gear 270 for cyclic meshing engagement with gear 272. Member 273 is retained in this operative position by detent 277 until the dividend and the divisor have been properly aligned.

As previously described, the counter-clockwise rocking movement of division actuator 164 (Fig. 5) also serves, through link 177 (Fig. 3), to rock the division setting lever 179 clockwise, thereby connecting lever 179 with plus-minus slide 73 when the cam portion of the yieldable pawl 191 is effective to condition the machine for a subtractive registration in the accumulator. Link 177 is also operative, through bellcrank 183 and clutch control slide 61, to edect engagement of the clutch and closing of the motor contacts.

Referring now to Fig. 6, shaft 271 has a two-position cam 285 secured thereto for intermittent counter-clockwise rotation with gear 270 (Fig. 5). Since, with the depression of division control key 15e, gears 47 have been moved into meshing engagement with gears 48 for a subtract operation, the first machine cycle rotates gear 27) and cam 285 counter-clockwise 180 to disenmesh gears 47, 48 and engage right shift collar 125 with its associated gear sleeve 129 thereby effecting one ordinal shift of the register to the right. With the centralization of the gears 46, 47, pawl 191 (Fig. 3) is caused to yield as lever 179 is maintained in its set position of cam 21MB. At the very end of the rst 180 rotation, cam 285 releases the right shift collar to its inoperative position under the urgency of spring 142, and spring 195, through pawl 191, reengages gears 47 and 48. rthe second machine cycle then operates, through gear 27d, to rotate cam 28S a second 180 to effect one subtraction of the divisor in the keyboard from the dividend in the register. To enable this sequence of operations, a cam follower arm 286 is pivotally mounted at 2257 on said frame 13 and carries a roller 288 which is maintained in active engagement with cam 285 by a spring 229. At its upper eX- tremity, arm 286 has a rearwardly extending link 295B pivotally secured thereto at 291. Link 290 has an elongated slot 292 in the rearward end thereof embracing a stud 293 on an arm 294 which is secured to shaft 77 for selective control thereof. Slot 292 is of suicient length to permit rocking movement of the plus-minus gear strap 78 in either direction. With the clockwise rocking of strap 78 and shaft 77 upon initiation of a division operation, the stud 293 is moved into abutting relation with the forward end of slot 292 and the cam 2255, in the first rotation thereof, is effective, through arm 28o and link 29d, to restore the strap 78 and therefore gears 46, 47 to their centralized position. With this centralization of the strap 78, plus-minus slide 73 (Fig. 3) is moved rearwardly when pawl 191 is caused to yield against the urgency of its spring 195. To control the engagement of the collar 127 with the gear sleeve 129 for a right shift of the register, the push rod 141 (Figs. 4 and 6) carries a disk 295 which is maintained in engagement with an arm 296 by a spring 142. Arm 296 is pinned to, and roekable with, shaft 297 journalled at its ends in brackets 293 secured to cross-member 1111. Also secured on shaft 297, intermediate its ends, is an arm 299, the upper end of which is in abutting relation with a stud 3d@ on the link 290. It is therefore readily apparent that a rearward movement of the link 29d is effective to rock arm 299, shaft 297 and arm 296 counter-clockwise, as viewed in Fig. 6, to translate push rod 141 rearwardly of the machine, thereby engaging clutch collar .127 with gear sleeve 129 to enable a right carriage shift.

' Following the inwardly rocked movement of the member 273, when the upper arm 276 thereof is moved into abutting relation with the end of shaft 2411 and the lower arm thereof is elfective to move gear 270 into the path of mutilated gear 272, each two successive machine cycles becomes effective with the first 180 rotation of cam 285 to centralize the plus-minus gears 46, 47 and initiate a right shift of the carriage; and, in the second 180 rotation, the cam 285 is operative to effect a subtractive registration in the register. This program sequence continues until the register has been shifted to the right to a position where the subtraction `of the divisor from the dividend creates an overdraft. The ovedraft thus created functions in a conventional manner, as previously described, to translate shaft 201 and gear 227 to the right, as viewed in Fig. 4. This overdraft controlled movement of the shaft 201 serves, through upper arm 276 (Figs. 4 and 5), to swing forked member 273 and therefore gear 270 outwardly to its inoperative position. Simultaneously, the gear 227 is moved into the path of its mutilated gear 228 and the division program control device then becomes effective to carry out the automatic division operation. During the aligning phase of the operation controlled by the mechanism just described, the subtract cycle in each ordinally shifted position of the accumulator is registered in the revolutions counter. Therefore, it can be seen that upon the occurrence of the overdraft, when the division operation proper is initiated, a partial quotient appears in the counter wheels 106. With a partial quotient having been registered in the counter during the aligner phase of the operation, 'the number of cycles required to complete the automatic division operation is considerably decreased.

Operation In the machine embodying the invention described hereinbefore, the overdraft responsive mechanism is associated with the second positively actuated order beyond the keyboard. For example, in a machine having a tenorder keyboard, the predetermined overdraft responsive order is the twelfth order of the machine. Therefore, with the register carriage in its leftmost position, which position it automatically assumes upon termination of each division operation, a dividend with the highest digit thereof, four orders to the left of the keyboard followed by two or more zeros and with the highest digit of the divisor in the leftmost order of the keyboard, the resulting quotient would be erroneous. The mechanism will, however, properly align any value of thirteen digits entered or -standing in the rightmost dials of the register with a value set in any of the ordinal rows ofl keys in the keyboard.

In the operation of a calculating machine embodying an automatic division aligner constructed and operated in accordance with the instant invention, a depression of division key 150 conditions the automatic division mechanism by releasing latch member 163 (Fig. 5) thereby eecting a rocking movement of division actuator 164 under the urgency of spring -169. Rocking of actuator 164 serves two functions, first to move division setting lever 179 (Fig. 3) into engagement with plus-minus slide 73 whereby the yieldable pawl 191 is effective to condition the machine for subtractive operation. The movement of setting lever 179 also serves to effect engagement of the clutch and closing of the motor contacts and to rock shaft 205, thereby operatively positioning the free end of link 210 with respect to plate portion 213 of lever member 214. Setting lever 179 and the mechanism controlled thereby is continuously maintained in an operative position by the latch 218 (Fig. 2) until the completion of the automatic division operation.

The second function controlled by the rocking of division actuator 164 is to condition the machine for an aligning operation by camming member 273 (Fig. 5) inwardly of control plate 58, thereby moving gear 270 into the path of mutilated gear 272 and positioning the upper arm 27d of member 273 into abutting relation with the end of shaft 201.

During the alignment phase of the division operation, the two-position cam 285 (Fig. 6) is immediately rotated counter-clockwise, in the first machine cycle, to rock cam follower 286 counter-'clockwise thereby moving link 200I rearwardly rocking shaft 77 to centralize plus-minusl gears 46, 47. With this rocking of shaft 77, pawl 191 yields with the rearward movement of silde 73. Simultaneously, the link 290 serves to engage the right shift clutch for one ordinal shift of the register. In the second machine cycle, the cam 285 enables the restoration of follower 2&6 to its initial position when spring 195 and pawl 191 (Fig. 3) returns plus-minus slide 73 to its subtractive position. The divisor is therefore subtracted once from the dividend during this cycle and the cyclic count is registered in the revolutions counter forming a part of the quotient. In the third cycle, cam 285l again operates to centralize the plus-minus gears and enable an ordinal right carriage shift. A subtractive operation is again effected by the second rotation of the cam in the fourth cycle and this sequence of operation continues until an overdraft occurs, with each subtractive cycle being registered in the counter as a partial quotient. The highest significant digits of the dividend and divisor will therefore be automatically brought into alignment in this manner prior to the outset of the division operation.

Immediately upon the occurrence of the overdraft, roller 224 of disk 225 (Fig. l) engages lever member 214 to translate shaft 201, cam 226, and gear 227 to the right, as viewed in Fig. 4. This translation of shaft 201 swings member 273 and therefore gear 270 to its inoperative position and moves gear 227 (Fig. 5) into operative relation with mutilated gear 228 for conventional control of the ensuing automatic division phase -of the operation.

I claim:

l. In a calculating machine, a dividend register 'and and an actuating means therefor, 'a divisor receiving means, means for shifting said register relative to said divisor receiving means, means for controlling positive and negative registrations on said register by said actuating means, an automatic division mechanism including a normally inoperative mutilated gear operative to control operation of said positive and negative registration control means and said shifting means to divide a dividend in said register by a divisor in said divisor receiving means `and an overdraft sensing means operative to position said mutilated gear in its operative position, and means for aligning a dividend in said register withl a divisor in said receiving means comprising the combination of a manually `operable means for setting said controlling means for a negative registration, a normally disabled program means, including a second mutilated gear operative to control the operation of said controlling means and said shifting means for effecting alternate cyclic operation thereof, a driving connection for said program means for effecting continuous operation thereof, means rendered effective by said manually operable means to enable said driving rconnection to initiate the sequence of operations determined by said program means, and means controlled by said overdraft sensing means for disabling said program means and for positie-ning said first mutilated gear to initiate a division operation.

2. In a calculating machine, a dividend register, a divisor receiving means, means for ordinally shifting said register relative to said divisor receiving means, means movable in either direction from an inactive position thereof to determine additive or subtractive registrations on said register, a cyclically operable actuating means, and a mechanism for aligning a dividend in said register with a divisor in said receiving means comprising in combination: a settable member for moving said movable means to a subtract position, aresilient member associated with said settable member and operable lto restore saidirnovable means to its subtract position upon displacement therefrom, a` two position cam for moving said movable means to its inactive position and effecting ordinal operation of said shifting means, said cam being normally positioned to determine subtractive registrations, a normally inactive gear positionable to control said cam, a mutilated gear driven cyclically by said actuating means and meshing with said control gear in the active position thereof, positionable means 4for moving said control gear into operative relation with said mutilated gear, the driving of said control gear by said multilated gear operating through said cam to successively enable a subtract registration on said register and to inactively position said movable means and enable an ordinal shifting of said register until an overdraft registration occurs, a detent means for restraint of movement of said positionable means in the operative or inoperative position thereof, a manually operable means for setting said settable member and moving said positionable means to its operative position, and means operable upon an overdraft registration to restore said positionable means to its inoperative position.

3. ln a calculating machine, a register in which -a dividend is entered, a divisor receiving means, means for ordinally shifting said register in either direction relative to said divisor receiving means, means movable in either direction from a neutral position thereof to determine additive or subtractive registration on said register, a revolutions counter mechanism, means operable by said movable means With the movement thereof to control operation of said revolutions counter mechanism, a cyclically operable actuating means, an automatic division control mechanism including a cam having three operative positions corresponding to the three operative positions of said movable means, said cam being normally positioned to determine subtractive registrations, a settable member associated with said cam for controlling said movable means, a control shaft for mounting said cam shiftable endwisc to and from operative position, overdraft control means for causing shifting of said shaft to its operative position, a gear on said shaft, a first mutilated gear driven cyclically by said actuating means and meshing with said shaft gear in the operative position of said shaft, the driving of said shaft by said gears operating through said cam to determine correction o-f an overdraft, shifting of the register in one direction with said movable means in its neutral position, and resetting of said movable means to its subtract position, `and a dividend aligning mechanism comprising the combination of, a manually operable means for setting said settable member to position said movable means for subtractive registrations, a resilient member associated with said settable member and operable to restore said movable means to its subtract position upon displacement therefrom, a two position cam for effecting a subtractive registration on said register in one position thereof and for moving said movable means to its neutral position and causing an ordinal shift of the register in the other direction in the second position thereof, each such subtractive registration being registered on said revolutions counter, a normally inactive gear for controlling said cam, a second mutilated gear driven cyclically by said actuating means in combination with said first mutilated gear and meshing with said controlling gear in the active position thereof, means positionable by said manually operable means for movingsaid controlling gear into operative relation with said second mutilated gear, the driving of said controlling gear by said second mutilated gear operating through said two position cam to successively enable a subtractive registration on said register and `a count in said revolutions counter, and a shifting of said register with said movable means in its neutral position, and means operable by said register in the aligned position of the dividend and the divisor to initiate operation of said overdraft control means for shifting said control shaft to its operative position to restore lo said positionable means to its inoperative position thereby initiating a division operation.

4. ln a calculating machine, a divident register, divisor receiving means, means for ordinarily shifting said register relative to said diviso-r receiving means, means movable in either direction from an inactive position thereof to determine additive or subtractive registrations on said register, a cyclically operable actuating means controlled by said divisor receiving means to operate said register additively or subtractively as determined by said movable means, an automatic division mechanism including a normally inactively positioned division program control device, means associated with said program control device for controlling the operation of said movable means and said shifting` means, a rst mutilated gear driven by said actuating means to control said program control device in the active position thereof, an overdraft controlled means operable to actively position said program control device,.and a mechanism for aligning a dividend in said register with a divisor in said receiving means comprising in combination: `a settable member fo-r moving said movable means to a subtract position, a resilient member associated with said settable member and operable to restore said movable means to its subtract position upon displacement therefrom, a two position cam for moving said movable means to its inactive position and effecting ordinal operation of said shifting means, said cam being normally positioned to determine subtractive registrations, a normally inactive gear positionable to control said cam, a second mutilated gear cyclically driven by said actuating means and meshing with said control gear in the active position thereof, positionable means for moving said control gear into operative relation with said second mutilated gear, said control gear operating successively to effect asubtractive registration on said register, to inactively position said movable means and enable ordinal operation of said shifting means to align the dividend and divisor for operation of said overdraft controlled means, and means operable by said overdraft controlled means and said program control device to restore the said control gear to its inactive position upon initiation of the operation of said division mechanism.

5. ln ya calculating machine having `a dividend register, an actuating means therefor; a divisor receiving means, means for ordinally shifting said register in either direction relative to the divisor receiving means, adjustable means for sign character control of registrations on said register by said lactuating means, an automatic division control mechanism, an overdraft mechanism for initiating operation of said division control mechanism and means operable thereby to lalternately control said adjustable means and said shifting means for moving said register in kone direction, a control key, and means operable by said key to initially condition said division control mechanism to adjust said adjustable means for a negative registration and to initiate operation of said actuating means: a. normally inoperative bi-cyclic program control device settable by said lrey operable means to sequentially disable said adjustable means and effect operation of said shifting means to shift said register in the other direction in the first of each two cycles and to enable said adjustable means to effect a negative registration on said register in the second cycle of each two cycles, such operational sequence continuing to an overdraft, and means operable by said overdraft mechanism to restore said program control device to its inoperative position and to initiate operation of said division control mechanism.

6. ln a calculating machine having a dividend register, actuating means therefor, a divisor receiving means, means for bidirectionally shifting said register relative to said divisor receiving means, means adjustable to control the sign character registration on said register by said actuating means, settable means engageable with said adjustable means to control the adjustment thereof, a division program control device associated. with said settable means operable to control the operation thereof and to effect unidirectional operation of said shifting means, an overdraft control means operable to initiate operation yof said program control device, and a control key for engaging said settable means and initiating operation of said actuating means, a dividend alignment mechanism comprising a bi-cyclic control means rendered operable by said key and operative in alternate cycles of operation to respectively render said settable means inoperable and effect operation of said shifting means to shift said register in the other direction to a position determined by said divisor receiving means and to enable operation of said settable means to effect a negative registration on said register, and means operable by said program control device upon operation of said overdraft control means to disable said bi-cyclic control means.

7. In a calculating machine having a register for receiving a dividend and an actuating mechanism therefor, a divisor receiving means, la member settable to a plurality of positions to control registration and the sign character thereof by said actuating mechanism on said register, means for ordinally shifting said register in either direction relative to said actuating mechanism, an automatic division control mechanism comprising a program control device for automatically enforcing a predetermined sequence of machine operations including means for controlling said settable member and means for initiating operation of said shifting means for moving the register in one direction, and overdraft means for enabling operation of said program control device: a bi-cyclic control means for aligning a dividend and divisor `operable in alternate cycles to initiate operation of said shifting means to move the register ordinally in the other direction and to control the setting of said settable member for subtraction of the divisor from the dividend, a control key for initiating operation of said bi-cyclic means, thereby effecting movement of said dividend register to a position determined by said divisor receiving means to initiate operation of said overdraft means, and means operative by said overdraft means for disabling said bi-cyclic means and for enabling said program control device for initiating a division operation.

8. In a calculating machine having a dividend register and an actuating means therefor, a divisor receiving means, means for ordinally shifting said register relative to said divisor receiving means, and an automatic division mechanism including lan overdraft controlled means, a dividend aligning mechanism operable to align a dividend in said register with a divisor in said receiving means comprising in combination: normally inactive means operable by said division mechanism to control negative and positive registrations on said register, manually operable means for moving said inactive means to active position, a normally inoperative bi-cyclic controlled means operable to disable said normally inactive means in the first of each two successive cycles and to effect operation of said shifting means, means operable by said bi-cyclic controlled means in the second of each two cycles for rendering said inactive means operable to effect a negative registration in said register, each two successive cycles being operable to ordinally move said register to the overdraft position with respect to said divisor receiving means, means controlled by said manually operable means upon operation thereof to effect movement of said bi-cyclic controlled means to its operative position, and means operable upon the occurrence of an overdraft to disable said bi-cyclic controlled means land initiate operation of said automatic division mechanism.

9. In a calculating machine, a shiftable carriage, a first register in said carriage, actuating means therefor, means for entering a dividend in said first register, a divisor receiving means, a cyclically operable clutch for said actuating means, a second register in said carriage operable to register a quotient, a sig-n character control means for said first and said second register, means for ordinally shifting said carriage in either direction relative to said actuating means, a division control mechanism operatively positionable to automatically enforce a predetermined sequence of three machine operations including control of said sign character control means for addition and subtraction and for initiating operation of said shifting means in o-ne direction after each overdraft in said first register in a division operation, means driven by said cyclically operable clutch to control said division control mechanism in the operative position thereof, a dividend aligning mechanism engageable with said driven means to determine a two cycle alternate operational control for initiating operation `of said shifting means in the other direction and for controlling the said sign character control means to effect a partial registration of the quotient in said second register, a manually operable means effective to engage said dividend aligning mechanism with said driven means and to initiate operation of said cyclically operable clutc-h, and `an overdraft control means operable upon alignment of the dividend and divisor to disengage said aligning mechanism and to operatively position said division control mechanism.

l0. `In a calculating machine having a carriage, a dividend register in said carriage, differential `actuating me'ans therefor, a divisor receiving means for controlling differential operation of said actuating means, a quotient register in said carriage, an actuator for Said quotient register, means for ordinally shifting said carriage in either direction relative to said differential actuating means and said actuator, sign character control means for controlling the sign lcharacter of registration by said actuating means and said actuator in said dividend register and said quotient register respectively, means settable to effective position and adjustable to control the operation of said sign character control means for subtractive and additive registrations in said dividend register and unlike registrations in said quotient register, and a division program control device for automatically enforcing a predetermined sequence of machine operations during a division operation including adjustment of said settable means in the effectively set position thereof and the operation of said shifting means to move said carriage in one direction, a dividend aligner device comprising a bicyclically operable control means effective in alternate cycles todisable the adjustment of said settable means by the program control device in the effectively set position of the settable means and to effect operation of said shifting means to ordinally shift said carriage in the other direction, a manipulable means operable to set said settable means to effective position and thereby adjust Said sign character control means to effect subtractive registration in said dividend register, to initiate continuous cyclic Ioperation of said control means and said actuating means, and an overdraft control means operable to terminate operation of said control means and initiate operation of said program control device upon alignment of a dividend with a divisor and during the ensuing division operation.

References Cited in the file of this patent UNITED STATES PATENTS 2,365,507 Allen Dec. 19, 1944 2,408,097 Pott sept. 24, 1946 2,636,677 Gang Apr. 28, 1953 2,653,762 Ellerbeck Sept, 29, 1953 2,653,763 Hopkins Sept. 29, 1953 2,653,764 Hopkins Sept. 29, 1953 2,653,765 Machado et al Sept. 29, 1953 

